Friction draft-gear.



PATENTED JULY 30.1907.

A. LIPSGHUTZ.. FRIGTION DRAFT GEAR. APPLIUATIONHLED noms. 190e.

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PATENTED JULY 30, 19.07. A. LIPSGHUTZ. PRICTION DRAFT GEAR.

APPLIoAnoH FILED xov. an, 190e.

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PATENT OFFICE.

ARTHUR LIPSCHUTZ, OF CHICAGO, ILLINOIS.

FRICTION DRAFT-GEAR.

Specification of Letters Patent.

Patented .ru-1y 3o, 1907.

Application led November 22,1906. Serial No. 344,603.

To all whom it may concern:

Be it known that I, ARTHUR LrrseHU'rz, a citizen of the United States, and a resident of Chicago, Cook county, Illinois, have invented a certain new, useful, and Improved Friction Draft-Gear, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.l

My invention relates to improvements in friction draft gears or riggin gs for railway cars and has particular reference to improvements in draft gears for freight cars.

A friction draft gear of the class with which this invention is concerned, is distinguished from others by a transversely arranged spring or springs, which act upon followers through the medium of transversely movable wedge members. The frictional engagement of the wedge members and the followers which co-act therewith, supplements the springs in resisting both pulling and bufling strains. Such draft gears, while reliable under extreme compression in either direction, have been objected to, on the ground that they yield reluctantly to blows and strains incident to the coupling of cars, with the result that greater shocks are communicated to the cars, than when the ordinary spring draft gears or riggings are used. My investigations have led me to the conclusion, that the difficulty with the ordinary friction draft gear arises from the fact that the frictional resistance, or opposition thereof to the movement of the coupler, is substantially constant under all conditions, being but Aslightly increased by the compression of the spring.

With these observations in view, my purpose is tov provide a friction draft gear, or rigging, which shall retain the advantages of the present devices, but which shall be so constructed, as to insure an increase in its frictional resistance during compression, t. e., in proportion to the degree of compression, to the end that a lighter spring or springs may be employed in the rigging; to the end that the gear or rigging shall be sensitive and responsive to light blows or strains; to the end that the rigging shall yield readily to sudden shocks and shall gradually take up the force of said shocks, to the end that the intermediate members of the rigging shall interpose greater and greater resistance between the spring and the coupler, and ultimately absorb the whole force of the blow, before the spring is completely compressed; and to the end that the return of the various members to normal positions shall be quickly effected, when the rigging is relieved from the force tending to compress or collapse the same.

My invention consists generally in a friction draft gear or rigging, including suitable car sill stops, in combination with a coupler strap, fore and aft followers normally abutting respective stops, transversely movable members interposed between said followers, and, a

spring, or springs, arranged between said transversely movable members, and tending to project the same,

said followers and intermediate members being provided with engaging frictional surfaces, which conform to arcs of lesser and greater radii, respectively; whereby movement of one follower toward the other, within the strap, to compress the spring, steadily varies the angles of engagement between the intermediate members and the followers, markedly supplementing the compression resisting force of the spring.

My invention also consists in various details of construction, and in combinations of parts, all as hereinafter described and particularly pointed out in the claims. l

The invention will be more readily understood by reference to the accompanying drawings, forming a part of specification, in which;

Figure I, is a plan view of a draft rigging embodying my invention, showing the rear end thereof in section, upon the line lx, 1X, of Fig. 2; Fig. 2,

is a side elevation of the draft rigging, removed from the car sills, showing the rear portion of the rigging in section, upon the line 25', 2y, of Fig. I; Fig. 3, is a vertical transverse section, on the line 32, SZ, of Fig. l; Fig. 4, is a plan view of one of the followers; Fig. 5, is a plan view of one of the intermediate, or wedge members; and Fig. 6, is a diagrammatic, horizontal section upon a reduced scale, showing the gear, or rigging, as it appears when subjected to a pulling strain. Fig. 7, is a diagrammatic, horizontal section of my draft rigging, illustrating the manner of assembling the parts thereof.

As shown in the drawings, l, l, indicate the draft sills of a car. 2, 2, and 3, 3, are the pulling and bufling stops, respectively, secured upon the inner sides of said draft sills. 4, is the shank of a coupler, and 5 represents the coupler strap, U shaped inform, and having its end secured upon the rearend of the coupler shank. Within the strap 5, and between the stops 2, 2, and 3, 3, are arranged several members, which, when collapsed, oppose the movement of the coupler with respect to the sills, to such extent, as to take up the pulling and buffing strains to which the coupler is subjected. `These parts are few in number, comprising only the fore and aft followers 6 and 7 the two intermediate members 8 and 9, and the spring, or springs, l0. The followers are identical inform, and are interchangeable. This is true also of the intermediate members, 8 and 9. It will be noted that the intermediate members together, form a spring pocket, or chamber, 'for the spring l0, each thereof containing an internal spring recess, Il, (see Fig. 1 and 3). The members, 8 and 9, are wedgelike in form, but in lieu of straight inclined surfaces, usually provided on the corresponding members of other draft gears, I provide my intermediate members 8, with end surfaces, l2, which conform to arcs of circles having their centers outside of the outlines of said members. These are the arcs of greater radius before and hereinafter referred to. The followers, (i and 7, are provided with corresponding curved surfaces, 13, which conform to arcs of less radius than the surfaces of the intermediate members. The arcs of the surfaces .i3 are the arcs of lesser radius before and hereinafter referred to. The recesses 14, within the followers, accommodate the ends of the intermediate members, S, which ends normally engage intermediate portions of the curved surfaces, 13, on the followers, as shown in Fig. 1. vAt such times, the followers engage respective stops, 2 and 3, and, while the spring and intermediate members exert a heavy distending force upon the followers, the device as a whole, is nevertheless in condition to respond to a comparatively light blow or pull from the coupler. Fig. 1 of the drawings, discloses the reason for this condition. Referring to the saine, it will be noted that the intermediate menibers, which are constantly projected by the heavy spring, here engage the followers upon sharply acute angles. 1n consequence, a light force exerted upon either follower, is sufficient to drive the saine upon the intermediate members, an action which is re-prodiiced at the opposite follower, A. considerable longitudinal movement of the follower may take place, without much movement of the intermediate members, hence, before the springl will be compressed to any considerable extent, but, as the followers are further forced (lonL gitudinally) upon the intermediate members, the angles of frictional engagement and resistance between the members 8, 9, and 6, 7 become more and more abrupt, until angles, approaching degrees, with relation to the longitudinal axis of the device, are reached, with consequent maximum compression of the spring and maximum resistance to further movement of the parts. Such action of the rigging is well illustrated in Fig. G, which shows the members as they appear, when subjected to the pull of the coupler. The frictional opposition of the rigid members of the rigging, increases in substantially the same ratio as the resistance of the spring, and it will be seen that the total resistance of the rigging to longitudinal movement of the coupler, is at all times proportional to the degree of movement, and the force which imparts such movement. Any vforce which tends to compress the members of the rigging, is at first only slightly opposed thereby, but continuing, is increasingly opposed, first, by the increasing compression force of the spring, and second, by the increasing friction of the engaged rigid parts, or elements, due to the variation in the angles of engagement between these parts. lt is obvious that compression of the rigging in one direction, has the same effect as compression from the opposite direction. When, after being subjected to compressive force, the rigging is suddenly relieved, the then abruptly engaged surfaces of the rigid elements insure the quick return of the parts to normal condition. Here, again, a further advantage is to be noted, in that the angles of engagement increase in acuteness, as the members return to normal, and hence, the spring becomes less and less effective to distend the followers, so that the sudden snapping back, or recoil, of the parts, is prevented.

rIlie co-acting, rigid members of my draft rigging are rendered still more efficient by eorrugating the curved friction iiieinbeis.

surface thereof, as shown in Figs. l., 2, ll, and 5. The eorrugations l5, of one, fit the corrugations lti, of tlie other, increasing the length of the lines, or surfaces. of engagement between the parts, thereby adding to the durability thereof, and increasing their effectiveness as Any desired means, such as top and bottom bars, or flanges, 18 and 19, extending between Y tlie stops 2, and 3, may be employed for supporting the rigging between the draft sills.

.Each follower is provided with a vertical wedge sur face, 17, to facilitate the assembling of the parts witliin the strap. The edges of the followers may be easily` placed within the strap, after which, the follower may be driven into the same, against the force of the spring. which is thereby kplaced under considerable initial compression. The `wedge surfaces, 17, serve a useful purpose, as stated, but I prefer not to rely upon tlie same as the means for compressing the frictional niembers to the extent necessary for their insertion within the strap. As a better means of compressing the licavy spring, 1 employ a short bolt 19, which is inserted through holes 21, provided in the intermediair` meinbers, 8 and 9. By means of a nut, 22, on the bolt. the members 8 and 9 may be forced together sufficiently to permit the followers to collapse upon them as shown in Fig. 7. The dotted lines, 23, of Fig. 7, and the distances between the saine and the ends of tlie followers. show liow great may be the compression of the spring. When the friction members have been thus relatively compressed and secured, they may readily be set or placed within the strap 5, after which the bolt l t) is removed, permitting the spring to expand, and force tlie followers into engagement with the end of the coupler and the end of the strap; whereupon, the rigging as a` whole is ready to be placed between the draft sills of the car. The openings, 2l, in the intermediate followers. are concentric with the contained spring; hence, practically any bolt that may be at hand may be utilized in assembling or disinembering the draft rigging.

As various modifications of my invention will readily suggest themselves to one skilled in the art, l do not, confine the invention to the specific draft rigging lierein shown and described.

Having thus described my invention, l claim as new and desire to secure by Letters Patent:

l. ln a friction draft gear, a coupler and :i strap in cour hinzition with two ri id stop-engaging followers arranged in opposite ends of said sti-ap, intermediate members wien engaging botli followers, a spring forcing said intermediate members against said followeis and tending to force sait! followers apart, the coacting surfaces of said followers and members being formed to constantly engage upon single transverse lines only.

2. ln a friction draft gear, :i coupler :ind strap, in combination with stop engaging followers arranged in the ends of said strap, transversely movable intermediate members, a compression spring between said intermediate `membersy and said followers and intermediate members4 fl t) t) ll t) bination with followers arranged in said strap, intermediate transversely movable members engaged with said followers, a transverse spring and the engaging surfaces of said followers and intermediate members being corrugated and conforming to arcs of lesser' and greater radii respectively, substantially as described.

5. In a friction draft gear, a coupler and strap, in combination with draft sills and stops, followers in said strap and engaged with respective stops, intermediate transversely movable members between said followers, means tending to force said intermediate members against said followers to project the latter and said intermediate members and said followers being provided with engaging curved surfaces which conform to ares of greater and lesser' radii respectively, substantially as described.

G. In a friction draft gear, a coupler and strap, in combination with draft sills and stops` followers in said strap engaged with said stops, intermediate transversely mov able members between said followers, means tending to force said intermediate members against said followers to project the latter and said intermediate members and said followers being provided with engaging curved corrugated surfaces which conform to arcs of greater and lesser' radii, respectively, substantially as described.

7. In a friction draft gear, a coupler and strap, in combination with draft sills and stops, followers in said strap engaged with said stops, intermediate transversely movable members between said followers, means tending to force said intermediate members against said followers to project the latter, said intermediate members and said followers being provided with engaging curved corrugated surfaces which conform to arcs of greater and lesser radii, respectively and said followers being provided with end wedge surfaces, as and for the purpose speciiied.

8. In a friction draft gear, a coupler and strap, in com` bination with followers arranged' in said strap, intermediate members, a transverse spring between said intermediate members, said intermediate members being provided with holes to receive a temporary bolt, whereby the same may be contracted, to facilitate the insertion of the followers and members within said strap, and the engaging surfaces 'of said followers and said intermediate members conforming to arcs of lesser and greater radii, 1'espectively, substantially as described.

In testimony whereof, I have hereunto set my hand, this 17 day of November, 1906, in the presence of two subscribing witnesses.

ARTHUR LIPSCHUTZ.

Witnesses:

CHARLES GILm-m'r HAwLnY, R. W'. NELSON. 

